1. Field of the Invention
The present invention generally relates to a device and method for removing a tree, and specifically to a hydraulic device that may be coupled to a tractor and used to eradicate a mesquite tree.
2. Background of the Invention
In the Southwest, farmers and ranchers fight a constant battle against mesquite trees (genus Prosopis) “mesquites”. Mesquites propagate in pastures and fields very prolifically. Many farmers and ranchers consider mesquite trees a nuisance because they have very sharp thorns, sometimes as long as two inches. These needle-like thorns can injure cattle, horses, and livestock. Additionally, mesquites compete with native pasture for water and nutrients. A mesquite can thrive in very dry climates because of an extremely long tap root which can reach the water table, sixty or more feet below the surface.
Because of their particular biological makeup, mesquites are difficult to eradicate. Conventional methods for removing or reducing mesquite populations include mechanical treatment such as grubbing, chaining, shredding, or roller chopping. However, such methods are often unsuccessful because a mesquite has root buds below the surface. Unless these root buds are eliminated, the tree will regrow and send up multiple shoots upon injury or damage to the main trunk. Therefore, a mesquite cannot be permanently removed simply by cutting off the tree at its trunk as may be done with most other trees. Other efforts to remove mesquites include chemical treatment. However, such methods are expensive, potentially damaging to the environment, and often ineffective.
The present disclosure provides a device and method which may be used to sever a mesquite tree trunk while also disrupting the roots and root buds such that the mesquite will not re-grow. The device can be coupled to a tractor or loader having hydraulic lifting arms such as those commonly found on utility tractors or other machinery known as “skid steer loaders”, or, alternatively may be coupled to an excavator or other device adapted to be coupled to “skid steer” type attachments. The device, in some embodiments, may be adapted to be attached to a “3 point” hitch such as are found on conventional tractors and equipment.
The device comprises a housing comprising vertical walls, shaft, base plate, stabilizing portion, motor, and bit assembly. The housing comprises a coupling plate which may be coupled to a cooperative attachment plate of a tractor. The shaft extends vertically from the motor to the base plate at a lower end of the housing. The bit assembly is coupled to the lower end of the shaft. The stabilizing portion comprises a tubular member extending from the baseplate. At the lower end of stabilizing portion is a plurality of notches defining teeth.
In operation, the device may be positioned over a tree such that the tree is bent from a vertical position to a horizontal position and such that the stabilizing portion substantially surrounds the base of the tree. The tree trunk remains secured under the stabilizing portion as the shaft, together with the bit assembly, are caused to rotate in a clockwise direction and move downward, such that a hole is formed in the area below the base of the tree and the root ball and roots are destroyed by the turning bit assembly. The bit assembly comprising cutting and lopping portions, rotates within stationary stabilizing portion, and lops off any material, including the tree trunk, extending between the teeth as the lopping portions are moved to a position adjacent to the teeth. Dirt, roots, and other debris disturbed by the rotating bit assembly generally remain in the hole defined by the device or become confined within the stabilizing portion cavity. Upon sufficient agitation of the roots and root ball, the rotating bit assembly is caused to rotate in a counter-clockwise direction. This counter-clockwise movement along with upward movement of the shaft and bit assembly dislodges dirt, roots, and debris from the cavity such that the hole becomes filled and only a small mound remains following completion of the operation.
3. Description of the Prior Art
A number of patents and patent publications teach tree removal or grinding devices. For example, Anderson U.S. Pat. No. 1,012,962 teaches a device for “exterminating” stumps whereby the inside and the outside of the stump is acted on at the same time in order to cut away and destroy the stump. Moore U.S. Pat. No. 1,114,505 teaches a device for removing tree stumps whereby a cutter-head severs the roots of the stump so that the stump may then be extracted with a lift. Moore U.S. Pat. No. 1,164,659 teaches a stump removal device characterized by a centering cutter to enter the stump to center and steady the cutter head as it advances into the stump. Ferri U.S. Pat. No. 3,307,643 teaches an apparatus for the removal of tree stumps which cuts off the roots of a felled tree and then removes the stumps from the ground. Bodine U.S. Pat. No. 3,914,883 teaches a cutter blade structure which may be placed around the trunk of a tree to be harvested, and the blades thereof are driven vertically downwardly into the earth to sever the roots of the tree. Mozer U.S. Pat. No. 4,637,442 teaches a machine for coring stumps which includes an area for receiving a tree stump that has been removed from the ground. Lawson U.S. Pat. No. 8,006,726 teaches a tree stump coring apparatus comprising an elongated cylindrical cutting blade of a hollow rotatable tubular body. Kline, U.S. Patent Publication 2012/0111453 teaches a tree stump removal device comprising an annular housing having cutters to sever some or all of the horizontal roots extending from the tree stump. German patent Gerloff, DE 3441520 and French patent FR 2561062 teach a root grubbing device comprising a rotating circular cutting member that severs the roots so that the stump may be removed from the ground. Soviet Union patent Mojseenko, SU 1641228 teaches a stump removal device that cuts the lateral roots so that a lifter can raise the stump from the ground. Soviet Union patent Berzinsh, SU 458309 teaches a tree stump extractor, consisting of a rotary cylindrical cylinder. Soviet Union patent Novoselov, SU 709034 teaches a tree grubber mounted to a tractor and a cylinder which may be driven downward so that the stump may be extracted.
However all of the aforementioned devices are relatively complicated and unsuitable for removing trees with root balls, such as mesquites. What is needed is a device and method which may be used to easily sever a mesquite tree trunk and sufficiently disrupt the root and root ball systems such that the tree will not re-grow, and which will leave the soil in a relatively undisturbed condition following use.